External roller shutters as window insulation

Piwoslaw · 02-03-12, 03:48 PM

Over at my Grandma's house we had external roller shutters installed a few years ago. The ribs ("laths") are two layers of metal with polyurethane foam in between. When purchasing we got the medium-thick option (4mm) as a compromise between cost and insulation value. Today I'd have gotten the thickest possible, but that was then...
Today I checked exactly how much they insulate from the cold. I closed one and left the other open as a comparison.

The indoor temperature was 17°C, outdoor was -20°C, so the differential was quite large. The windows are already double pane and argon filled, so their insulation value is already high, but adding more insulation on the outside will always help. Here is the temperature distribution for the two windows:

The external roller shutter also noticeably reduces the drafts that can be felt when standing next to the window.

These roller shutters have more virtues: In the summer they are GREAT at reducing solar gain (these are facing south), while at night they can be slightly raised to allow ventilation:

A locking mechanism at the bottom keeps them from being lifted from the outside, so it is safe to open a window for the night.

They also function quite well as storm shutters. I'm using that arguement to talk Grandma into mounting shutters on the west-facing windows, where the worst storm winds cause the windows to leak.

02-03-12, 03:48 PM	#1
Piwoslaw Super Moderator Join Date: May 2009 Location: Warsaw, Poland Posts: 961 Thanks: 188 Thanked 110 Times in 86 Posts	External roller shutters as window insulation Over at my Grandma's house we had external roller shutters installed a few years ago. The ribs ("laths") are two layers of metal with polyurethane foam in between. When purchasing we got the medium-thick option (4mm) as a compromise between cost and insulation value. Today I'd have gotten the thickest possible, but that was then... Today I checked exactly how much they insulate from the cold. I closed one and left the other open as a comparison. The indoor temperature was 17°C, outdoor was -20°C, so the differential was quite large. The windows are already double pane and argon filled, so their insulation value is already high, but adding more insulation on the outside will always help. Here is the temperature distribution for the two windows: The external roller shutter also noticeably reduces the drafts that can be felt when standing next to the window. These roller shutters have more virtues: In the summer they are GREAT at reducing solar gain (these are facing south), while at night they can be slightly raised to allow ventilation: A locking mechanism at the bottom keeps them from being lifted from the outside, so it is safe to open a window for the night. They also function quite well as storm shutters. I'm using that arguement to talk Grandma into mounting shutters on the west-facing windows, where the worst storm winds cause the windows to leak. Attached Thumbnails __________________ Ecorenovation - the bottomless piggy bank that tries to tame the energy hog.